I would recommend that your write a module that follows the pointers
generated by the drainage option of r.watershed. You should do this
int C, but you could do it using the shell and the neighborhood
modifiers in r.mapcalc.
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Michael Shapiro U.S. Army CERL
email: shapiro@zorro.cecer.army.mil Environmental Division
phone: (217) 352-6511 ext 526 P.O. Box 9005
fax: (217) 373-7222 Champaign, Ill. 61826-9005
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